Trad Gang

Main Boards => The Bowyer's Bench => Topic started by: Longtoke on May 10, 2025, 09:06:18 PM

Title: putting glass between lams?
Post by: Longtoke on May 10, 2025, 09:06:18 PM
I noticed one of my bows has a layer of glass in the middle of the lams.  what would the pros and cons of this approach be?  Has anyone else tried it?
Title: Re: putting glass between lams?
Post by: Crooked Stic on May 10, 2025, 09:35:10 PM
Prolly core tuff. They used to use it to stabilize. There is also uniweft (a woven glass for that also.
Title: Re: putting glass between lams?
Post by: B-JS on May 11, 2025, 04:28:26 AM
Pro: nice Colour accent, maybe a Bit torsional stability
Con: adds weight to the limb
Title: Re: putting glass between lams?
Post by: Kirkll on May 11, 2025, 01:17:17 PM
The lightest weight glass product you can use for torsional stability in the core is Stable Core. its only .015 thick. Seems to work best right under the glass on back side of the limb though... If its dead center of the core it's pretty much a cosmetic  racing stripe.

A thin twill or bias weave carbon works better for stability. For a rock solid light weight recurve i've used .015 twill over stable core on the back and got incredible torsional strength in a 30# radical recurve limb. It felt as stiff as a 60# limb torsionally.   Kirk
Title: Re: putting glass between lams?
Post by: Camp Creek on May 12, 2025, 08:42:23 AM
I don't see the point in that from a mechanical standpoint at all..  Fiberglass is denser than wood and the only point in adding that mass to the limbs is to provide strength.  The bending stresses are at a minimum in the center of the limb, so putting it there is pointless, and putting it at the back or belly would give the same torsional benefit.